DC-Link Capacitor Selection

Hi,

I would like to know how to select the value for the DC-link capacitor. I have read some articles and I have gained some understanding. It is mainly the ripple current rating of the capacitors that will be the deciding factor. But I do not know how to calculate the ripple current value for vector control (FOC). 

Is there any document that I can go through?

It would be great if someone can share their thoughts on this topic.

Thanks